An educated, rich man, and son of the Fifth Earl, Lord Mayo had served as the Viceroy and Governor General of India from 1869 1872. Mayo was of a much considerate rationale and took interest in the betterment of the residing Indians. The Lord had worked in several areas of administration, like finance, administering census, statistical survey, agriculture, commerce and of course in educational improvements. However, he being a Briton, and to top it, had visited the Cellular Jail. Lord Mayo had plans to construct a sanatorium for the inmates, and for that purpose he had plans to visit Mount Harriet. However, Sher Ali, a Pathan, was flared with the burning desire to kill a British officer of high rank, and consequently after much hindrances and strategies, was successful to slay the Lord.

Lord Mayo (1822-1872) was the Viceroy and Governor General of India from 1869 to 1872. Son of the Fifth Earl of Mayo, he was born on 21st February 1822, was christened Richard South well Bourke and graduated from Trinity College, Dublin. He had held the office of chief secretary for Ireland before Disraeli appointed him to succeed Lord Lawrence.

He inherited his father as the Sixth Earl and came to India as Lord Mayo. He continued the policy of Non-intervention followed by his immediate predecessors and through diplomatic manoeuvre secured the good will and friendship of Sher Ali, Ameer of Afghanistan, who met the viceroy at Ambala in 1869. Mayo secured the Russian recognition of the Oxus as the Northern Afghan border. Perhaps his great achievement was the reform of financial management. He increased the salt duty and income tax, enforced economy in the public administration, introduced decentralised finance with provision for fixed block grants for five years to the provincial governments and substantially improved the finances of the country. Formerly the centre controlled all finances and the provinces had to make out cases for allocation of funds and spent what they could get.

He consolidated the frontiers of India and reorganised the country's finances; he also did much to promote irrigation, railways, forests and other useful public works.

It was during Mayo's administration that the first general census in India was undertaken in 1870. He organised a statistical survey of the country and created the department of agriculture and commerce. While Mayo inherited serious deficits, untrustworthy estimates and accounts in arrears and statistics incomplete, he left behind substantial surplus, estimates worthy of confidence and accounts and statistics punctual and full. To educate the young sons of the Indian princes and chiefs he founded Mayo College at Ajmer.

In 1872 the superintendent of the Andaman Islands, General Stewart invited Lord Mayo, to visit the settlement in order to see for himself the progress made, in pursuance of his plans. The viceroy reached the Andaman Islands via Moulmein by H.M.S. Frigate Glasgow on the morning of 8th February 1872.

The prisoners had been kept at their regular tasks, but adequate provision was made for the viceroy's protection. The authorities had made special arrangements for his safety in quarters like Viper island and Ross Island. In the evening on that very day shortly before it was dusk, Lord Mayo decided to see Mount Harriet to determine the suitability of building a sanatorium for the convicts and also to enjoy the marvellous sunset. The party proceeded accordingly to Mount Harriet. After rounding off his official programme there, Lord Mayo sat down facing the west and looking across the sea at the setting sun.

While enjoying the scene, he was totally unaware that destiny was bringing him closer to the death-trap laid down by one Sher Ali. Sher Ali was a Pathan from the North Western Frontier. He was with the Punjab Mounted Police and was convicted at Peshawar for murder. His death sentence had been converted to expatriation for life, and was sent to the Andamans. On the basis of his good conduct in the jail he was placed by the authorities among the 'ticket-of-leave' at Hope Town. Sher Ali was deeply influenced by the Wahabi Movement. But in the booklet published by the Andaman and Nicobar Administration, Mohammed Sher Ali has been listed among the Wahabi rebels deported to the Andamans in 1860-70. Maulana Md. Jafar Ali Thanesvri who was in the Andamans during that time as one of the political prisoners and who had later published an autobiography in Urdu, wrote that for years Sher Ali had long been waiting to kill a white man of high rank and he acquired the opportunity to execute his plans. Perhaps he intended to kill both the viceroy and the superintendent on the fateful day.

Throughout the day, Sher Ali had tried his best to cross the waters and get across to the viceroy to lay his hands upon him, but he could not get permission to go to Ross island where Lord Mayo was putting up. In disgust, Sher Ali had almost given up hope for that day. But when Lord Mayo decided to go to Mount Harriet, it was as if fate had brought him to Sher Ali's trap. Without being observed, Sher Ali went up the hill when Lord Mayo was on his way up to Mount Harriet, but the former could not get the opportunity. He thought out a plan and after climbing down, he hid himself near the jetty at a place from where he could attack the viceroy.

As darkness set in, Lord Mayo accompanied by the torch bearers advanced towards the shore as the guests on board were excitedly awaiting the viceroy's return. Lady Mayo was feeling appallingly anxious for the safety of her husband. Peering intently through the darkness, she saw the party nearing the shore. She asked the bandsmen to strike up "Rule Britannia". Lord Mayo stepped quickly forward to descend the jetty stairs and board the launch.

The next moment, Sher Ali, with the speed of lightning pounced upon Lord Mayo and knifed him in the back incurably before he was caught. After awhile Sher Ali was brought on board where the dead Lord Mayo was lying. The foreign secretary, Captain Atichson, asked him as to why he had committed the murder. Without recoiling, he replied, "Khuda ne Hukm Diya" (God so wished it). Then he was asked who his accomplice was, and he answered, "Mem Shank Koi Admi Nahin, mem Sharik Khuda Hoi" (Among men I have no accomplice: God is my accomplice). Next morning when he was called to plead, he said, "Han, Mainne Kiya" (Yes, I did it).

Sher Ali was convicted by the chief commissioner, Port Blair, sitting as sessions judge, and he was sentenced to be hanged by the neck till death. The high court of Bengal confirmed that Sher Ali was executed at the Viper Island.